where to look up ClassIDs?

what's this?

[affter333]

Hi, the code below is directly copied from mail.yahoo.com

I wonder where people learn all those classID number
and what does it mean? anybody?

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document.write('<object classid="clsid:41695A8E-6414-11D4-8FB3-00D0B7730277" CODEBASE="javascript:dontGotIt();" ID="Ymsgr" width="1" height="1">');
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[Purple Martin]

What kind of object is it?

The class id is assigned by whoever originally wrote the object and it's player. For example, when you insert a Flash object, the class id is for the Flash Player and the codebase url tells the browser where to go to get the Player.

[korkus2000]

The spec says it is intended for a URI, but you can see that is not always followed.